Methods of Refining Natural Oil Feedstocks

ABSTRACT

Methods are provided for refining natural oil feedstocks. The methods comprise reacting the feedstock in the presence of a metathesis catalyst under conditions sufficient to form a metathesized product comprising olefins and esters. In certain embodiments, the methods further comprise separating the olefins from the esters in the metathesized product. In certain embodiments, the methods further comprise hydrogenating the olefins under conditions sufficient to form a fuel composition. In certain embodiments, the methods further comprise transesterifying the esters in the presence of an alcohol to form a transesterified product.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/590,737, filed Jan. 6, 2015, which is a continuation of U.S.patent application Ser. No. 12/901,829, filed Oct. 11, 2010, whichissued as U.S. Pat. No. 8,957,268 on Feb. 17, 2015, which claims thebenefit of priority of U.S. Provisional Application No. 61/250,743,filed Oct. 12, 2009. Each of the foregoing applications is herebyincorporated by reference as though set forth herein in its entirety.

BACKGROUND

Metathesis is a catalytic reaction generally known in the art thatinvolves the interchange of alkylidene units among compounds containingone or more double bonds (e.g., olefinic compounds) via the formationand cleavage of the carbon-carbon double bonds. Metathesis may occurbetween two like molecules (often referred to as self-metathesis) and/orit may occur between two different molecules (often referred to ascross-metathesis). Self-metathesis may be represented schematically asshown in Equation I.

R¹—CH═CH—R²+R¹—CH═CH—R²

R¹—CH═CH—R¹+R²—CH═CH—R²  (I)

wherein R¹ and R² are organic groups.

Cross-metathesis may be represented schematically as shown in EquationII.

R¹—CH═CH—R²+R³—CH═CH—R⁴

R¹—CH═CH—R³+R¹—CH═CH—R⁴+R²—CH═CH—R³+R²—CH═CH—R⁴+R¹—CH═CH—R¹+R²—CH═CH—R²+R³—CH═CH—R³+R⁴—CH═CH—R⁴  (II)

wherein R¹, R², R³, and R⁴ are organic groups.

In recent years, there has been an increased demand for environmentallyfriendly techniques for manufacturing materials typically derived frompetroleum sources. For example, researchers have been studying thefeasibility of manufacturing biofuels, waxes, plastics, and the like,using natural oil feedstocks, such as vegetable and seed-based oils. Inone non-limiting example, metathesis catalysts are used to manufacturecandle wax, as described in PCT/US2006/000822, which is hereinincorporated by reference in its entirety. Metathesis reactionsinvolving natural oil feedstocks offer promising solutions for today andfor the future.

Natural oil feedstocks of interest include non-limiting examples such asnatural oils (e.g., vegetable oils, fish oil, animal fats) andderivatives of natural oils, such as fatty acids and fatty acid alkyl(e.g., methyl) esters. These feedstocks may be converted intoindustrially useful chemicals (e.g., waxes, plastics, cosmetics,biofuels, etc.) by any number of different metathesis reactions.Significant reaction classes include, as non-limiting examples,self-metathesis, cross-metathesis with olefins, and ring-openingmetathesis reactions. Representative non-limiting examples of usefulmetathesis catalysts are provided below. Metathesis catalysts can beexpensive and, therefore, it is desirable to improve the efficiency ofthe metathesis catalyst.

In recent years, there has been an increased demand for petroleum-basedtransportation fuels. Concerns exist that the world's petroleumproduction may not be able to keep up with demand. Additionally, theincreased demand for petroleum-based fuels has resulted in a higherproduction of greenhouse gases. In particular, the airline industryaccounts for greater than 10% of the greenhouse gases within the UnitedStates. Due to the increased demand for fuel and increased production ofgreenhouse gases, there is a need to explore methods of producingenvironmentally-friendly, alternative fuel sources. In particular, thereis a need to explore methods of producing environmentally friendly fuelcompositions and specialty chemicals from a natural feedstock.

SUMMARY

Methods are disclosed for refining a natural oil feedstock through ametathesis reaction of the natural oil feedstock in the presence of ametathesis catalyst.

In one embodiment, the method comprises reacting a feedstock comprisinga natural oil in the presence of a metathesis catalyst under conditionssufficient to form a metathesized product, wherein the metathesizedproduct comprises olefins and esters. The method further comprisesseparating the olefins from the esters. The method further comprisestransesterifying the esters in the presence of an alcohol to form atransesterified product.

In certain embodiments, the method further comprises treating thefeedstock prior to reacting the feedstock, under conditions sufficientto diminish catalyst poisons in the feedstock. In some embodiments, thefeedstock is chemically treated through a chemical reaction to diminishthe catalyst poisons. In other embodiments, the feedstock is heated to atemperature greater than 100° C. in the absence of oxygen and held atthe temperature for a time sufficient to diminish the catalyst poisons.

In certain embodiments, the method further comprises separating themetathesis catalyst from the olefins and esters with a water solublephosphine reagent.

In certain embodiments, the metathesis catalyst is dissolved in asolvent prior to the metathesis reaction. In some embodiments, thesolvent is toluene.

In certain embodiments, the method further comprises hydrogenating theolefins to form a fuel composition. In some embodiments, the fuelcomposition comprises a jet fuel composition having a carbon numberdistribution between 5 and 16. In other embodiments, the fuelcomposition comprises a diesel fuel composition having a carbon numberdistribution between 8 and 25. In some embodiments, the fuel compositionis: (a) a kerosene-type jet fuel having a carbon number distributionbetween 8 and 16, a flash point between approximately 38° C. andapproximately 66° C., an auto ignition temperature of approximately 210°C., and a freeze point between approximately −47° C. and approximately−40° C.; (b) a naphtha-type jet fuel having a carbon number distributionbetween 5 and 15, a flash point between approximately −23° C. andapproximately 0° C., an auto ignition temperature of approximately 250°C.; and a freeze point of approximately −65° C.; or (c) a diesel fuelhaving a carbon number distribution between 8 and 25, a specific gravityof between approximately 0.82 and approximately 1.08 at about 15.6° C.,a cetane number of greater than approximately 40; and a distillationrange between approximately 180° C. and approximately 340° C.

In certain embodiments, the method further comprises oligomerizing theolefins to form at least one of: poly-alpha-olefins,poly-internal-olefins, mineral oil replacements, or biodiesel.

In certain embodiments, the method further comprises separating glycerinfrom the transesterified product through a liquid-liquid separation,washing the transesterified product with water to further removeglycerin, and drying the transesterified product to separate the waterfrom the transesterified product. In some embodiments, the methodfurther comprises distilling the transesterified product to separate atleast one specialty chemical selected from the group consisting of:9-decenoic acid ester, 9-undecenoic acid ester, 9-dodecenoic acid ester,individually or in combinations thereof. In some additional embodiments,the method further comprises hydrolyzing the at least one specialtychemical, thereby forming at least one acid selected from the groupconsisting of: 9-decenoic acid, 9-undecenoic acid, 9-dodecenonic acid,individually or in combinations thereof. In certain embodiments, thehydrolyzing step further yields alkali metal salts and alkaline earthmetal salts, individually or in combinations thereof, of the at leastone acid.

In certain embodiments, the method comprises reacting thetransesterified product with itself to form a dimer.

In certain embodiments, the reacting step comprises a self-metathesisreaction between the feedstock and itself. In other embodiments, thereacting step comprises a cross-metathesis reaction between alow-molecular-weight olefin and the feedstock. In some embodiments, thelow-molecular-weight olefin comprises at least one low-molecular-weightolefin selected from the group consisting of ethylene, propylene,1-butene, 2-butene, individually or in combinations thereof. In someembodiments, the low-molecular-weight olefin is an alpha-olefin. In oneembodiment, the low-molecular-weight olefin comprises at least onebranched olefin having a carbon number between 4 and 10.

In another embodiment, the method comprises reacting a feedstockcomprising a natural oil in the presence of a metathesis catalyst underconditions sufficient to form a metathesized product, wherein themetathesized product comprises olefins and esters. The method furthercomprises separating the olefins from the esters. The method furthercomprises hydrogenating the olefins under conditions sufficient to forma fuel composition.

In certain embodiments, the fuel composition comprises a jet fuelcomposition having a carbon number distribution between 5 and 16. Inother embodiments, the fuel composition comprises a diesel fuelcomposition having a carbon number distribution between 8 and 25. Insome embodiments, the fuel composition is: (a) a kerosene-type jet fuelhaving a carbon number distribution between 8 and 16, a flash pointbetween approximately 38° C. and approximately 66° C., an auto ignitiontemperature of approximately 210° C., and a freeze point betweenapproximately −47° C. and approximately −40° C.; (b) a naphtha-type jetfuel having a carbon number distribution between 5 and 15, a flash pointbetween approximately −23° C. and approximately 0° C., an auto ignitiontemperature of approximately 250° C.; and a freeze point ofapproximately −65° C.; or (c) a diesel fuel having a carbon numberdistribution between 8 and 25, a specific gravity of betweenapproximately 0.82 and approximately 1.08 at about 15.6° C., a cetanenumber of greater than approximately 40; and a distillation rangebetween approximately 180° C. and approximately 340° C.

In certain embodiments, the method further comprises flash-separating alight end stream from the metathesized product prior to separating theolefins from the esters, the light end stream having a majority ofhydrocarbons with carbon number between 2 and 4.

In certain embodiments, the method further comprises separating a lightend stream from the olefins prior to hydrogenating the olefins, thelight end stream having a majority of hydrocarbons with carbon numbersbetween 3 and 8.

In certain embodiments, the method further comprises separating a C₁₈₊heavy end stream from the olefins prior to hydrogenating the olefins,the heavy end stream having a majority of hydrocarbons with carbonnumbers of at least 18.

In certain embodiments, the method further comprises separating a C₁₈₊heavy end stream from the fuel composition, the heavy end stream havinga majority of hydrocarbons with carbon numbers of at least 18.

In certain embodiments, the method further comprises isomerizing thefuel composition, wherein a fraction of normal-paraffin compounds in thefuel composition are isomerized into iso-paraffin compounds.

In certain embodiments, the reacting step comprises a self-metathesisreaction between the feedstock and itself. In other embodiments, thereacting step comprises a cross-metathesis reaction between alow-molecular-weight olefin and the feedstock.

In another embodiment, the method comprises reacting a feedstockcomprising a natural oil in the presence of a metathesis catalyst underconditions sufficient to form a metathesized product, wherein themetathesized product comprises olefins and esters. The method furthercomprises hydrogenating the metathesized product thereby producing afuel composition and at least partially saturated esters. The methodfurther comprises separating the fuel composition from the at leastpartially saturated esters. The method may further comprise isomerizingthe fuel composition, wherein a portion of normal paraffins areisomerized into iso-paraffins, therein forming an isomerized fuelcomposition. The method may further comprise separating a center-cutfuel stream from the fuel composition or isomerized fuel composition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of one embodiment of a process to producea fuel composition and a transesterified product from a natural oil.

FIG. 2 is a schematic diagram of a second embodiment of a process toproduce a fuel composition and a transesterified product from a naturaloil.

DETAILED DESCRIPTION

The present application relates to methods of refining a natural oilfeedstock through the metathesis reaction of the natural oil feedstock.

As used herein, the singular forms “a,” “an,” and “the” include pluralreferents unless the context clearly dictates otherwise. For example,reference to “a substituent” encompasses a single substituent as well astwo or more substituents, and the like.

As used herein, the terms “for example,” “for instance,” “such as,” or“including” are meant to introduce examples that further clarify moregeneral subject matter. Unless otherwise specified, these examples areprovided only as an aid for understanding the applications illustratedin the present disclosure, and are not meant to be limiting in anyfashion.

As used herein, the following terms have the following meanings unlessexpressly stated to the contrary. It is understood that any term in thesingular may include its plural counterpart and vice versa.

As used herein, the term “metathesis catalyst” includes any catalyst orcatalyst system that catalyzes a metathesis reaction.

As used herein, the terms “natural oils,” “natural feedstocks,” or“natural oil feedstocks” may refer to oils derived from plants or animalsources. The term “natural oil” includes natural oil derivatives, unlessotherwise indicated. Examples of natural oils include, but are notlimited to, vegetable oils, algae oils, animal fats, tall oils,derivatives of these oils, combinations of any of these oils, and thelike. Representative non-limiting examples of vegetable oils includecanola oil, rapeseed oil, coconut oil, corn oil, cottonseed oil, oliveoil, palm oil, peanut oil, safflower oil, sesame oil, soybean oil,sunflower oil, linseed oil, palm kernel oil, tung oil, jatropha oil,mustard oil, pennycress oil, camelina oil, and castor oil.Representative non-limiting examples of animal fats include lard,tallow, poultry fat, yellow grease, and fish oil. Tall oils areby-products of wood pulp manufacture.

As used herein, the term “natural oil derivatives” may refer to thecompounds or mixture of compounds derived from the natural oil using anyone or combination of methods known in the art. Such methods includesaponification, transesterification, esterification, hydrogenation(partial or full), isomerization, oxidation, and reduction.Representative non-limiting examples of natural oil derivatives includegums, phospholipids, soapstock, acidulated soapstock, distillate ordistillate sludge, fatty acids and fatty acid alkyl ester (e.g.non-limiting examples such as 2-ethylhexyl ester), hydroxy substitutedvariations thereof of the natural oil. For example, the natural oilderivative may be a fatty acid methyl ester (“FAME”) derived from theglyceride of the natural oil. In some embodiments, a feedstock includescanola or soybean oil, as a non-limiting example, refined, bleached, anddeodorized soybean oil (i.e., RBD soybean oil). Soybean oil typicallycomprises about 95% weight or greater (e.g., 99% weight or greater)triglycerides of fatty acids. Major fatty acids in the polyol esters ofsoybean oil include saturated fatty acids, as a non-limiting example,palmitic acid (hexadecanoic acid) and stearic acid (octadecanoic acid),and unsaturated fatty acids, as a non-limiting example, oleic acid(9-octadecenoic acid), linoleic acid (9, 12-octadecadienoic acid), andlinolenic acid (9,12,15-octadecatrienoic acid).

As used herein, the term “low-molecular-weight olefin” may refer to anyone or combination of unsaturated straight, branched, or cyclichydrocarbons in the C₂ to C₁₄ range. Low-molecular-weight olefinsinclude “alpha-olefins” or “terminal olefins,” wherein the unsaturatedcarbon-carbon bond is present at one end of the compound.Low-molecular-weight olefins may also include dienes or trienes.Examples of low-molecular-weight olefins in the C₂ to C₆ range include,but are not limited to: ethylene, propylene, 1-butene, 2-butene,isobutene, 1-pentene, 2-pentene, 3-pentene, 2-methyl-1-butene,2-methyl-2-butene, 3-methyl-1-butene, cyclopentene, 1-hexene, 2-hexene,3-hexene, 4-hexene, 2-methyl-1-pentene, 3-methyl-1-pentene,4-methyl-1-pentene, 2-methyl-2-pentene, 3-methyl-2-pentene,4-methyl-2-pentene, 2-methyl-3-pentene, and cyclohexene. Other possiblelow-molecular-weight olefins include styrene and vinyl cyclohexane. Incertain embodiments, it is preferable to use a mixture of olefins, themixture comprising linear and branched low-molecular-weight olefins inthe C₄-C₁₀ range. In one embodiment, it may be preferable to use amixture of linear and branched C₄ olefins (i.e., combinations of:1-butene, 2-butene, and/or isobutene). In other embodiments, a higherrange of C₁₁-C₁₄ may be used.

As used herein, the terms “metathesize” and “metathesizing” may refer tothe reacting of a feedstock in the presence of a metathesis catalyst toform a “metathesized product” comprising a new olefinic compound.Metathesizing may refer to cross-metathesis (a.k.a. co-metathesis),self-metathesis, ring-opening metathesis, ring-opening metathesispolymerizations (“ROMP”), ring-closing metathesis (“RCM”), and acyclicdiene metathesis (“ADMET”). As a non-limiting example, metathesizing mayrefer to reacting two triglycerides present in a natural feedstock(self-metathesis) in the presence of a metathesis catalyst, wherein eachtriglyceride has an unsaturated carbon-carbon double bond, therebyforming a new mixture of olefins and esters which may include atriglyceride dimer. Such triglyceride dimers may have more than oneolefinic bond, thus higher olegomers also may form. Additionally,metathesizing may refer to reacting an olefin, such as ethylene, and atriglyceride in a natural feedstock having at least one unsaturatedcarbon-carbon double bond, thereby forming new olefinic molecules aswell as new ester molecules (cross-metathesis).

As used herein, the terms “ester” and “esters” may refer to compoundshaving the general formula: R—COO—R′, wherein R and R′ denote any alkylor aryl group, including those bearing a substituent group. In certainembodiments, the term “ester” or “esters” may refer to a group ofcompounds with the general formula described above, wherein thecompounds have different carbon lengths.

As used herein, the terms “olefin” and “olefins” may refer tohydrocarbon compounds having at least one unsaturated carbon-carbondouble bond. In certain embodiments, the term “olefin” or “olefins” mayrefer to a group of unsaturated carbon-carbon double bond compounds withdifferent carbon lengths. It is noted that an olefin may also be anester, and an ester may also be an olefin, if the R or R′ group containsan unsaturated carbon-carbon double bond. Unless specified otherwise, anolefin refers to compounds not containing the ester functionality, whilean ester may include compounds containing the olefin functionality.

As used herein, the terms “paraffin” and “paraffins” may refer tohydrocarbon compounds having only single carbon-carbon bonds, having thegeneral formula C_(n)H_(2n+2), where, in certain embodiments, n isgreater than about 20.

As used herein, the terms “isomerization,” “isomerizes,” or“isomerizing” may refer to the reaction and conversion of straight-chainhydrocarbon compounds, such as normal paraffins, into branchedhydrocarbon compounds, such as iso-paraffins. The isomerization of anolefin or an unsaturated ester indicates the shift of the carbon-carbondouble bond to another location in the molecule or it indicates a changein the geometry of the compound at the carbon-carbon double bond (e.g.cis to trans). As a non-limiting example, n-pentane may be isomerizedinto a mixture of n-pentane, 2-methylbutane, and 2,2-dimethylpropane.Isomerization of normal paraffins may be used to improve the overallproperties of a fuel composition. Additionally, isomerization may referto the conversion of branched paraffins into further, more branchedparaffins.

As used herein, the term “yield” may refer to the total weight of fuelproduced from the metathesis and hydrogenation reactions. It may alsorefer to the total weight of the fuel following a separation step and/orisomerization reaction. It may be defined in terms of a yield %, whereinthe total weight of the fuel produced is divided by the total weight ofthe natural oil feedstock and, in some embodiments, low-molecular-weightolefin, combined.

As used herein, the terms “fuels” and “fuel compositions” refer tomaterials meeting required specifications or to blend components thatare useful in formulating fuel compositions but, by themselves, do notmeet all of the required specifications for a fuel.

As used herein, the term “jet fuel” or “aviation fuel” may refer tokerosene or naphtha-type fuel cuts, or military-grade jet fuelcompositions. “Kerosene-type” jet fuel (including Jet A and Jet A-1) hasa carbon number distribution between about 8 and about 16. Jet A and JetA-1 typically have a flash point of at least approximately 38° C., anauto ignition temperature of approximately 210° C., a freeze point lessthan or equal to approximately −40° C. for Jet A and −47° C. for JetA-1, a density of approximately 0.8 g/cc at 15° C., and an energydensity of approximately 42.8-43.2 MJ/kg. “Naphtha-type” or “wide-cut”jet fuel (including Jet B) has a carbon number distribution betweenabout 5 and about 15. Jet B typically comprises a flash point belowapproximately 0° C., an auto ignition temperature of approximately 250°C., a freeze point of approximately −51° C., a density of approximately0.78 g/cc, and an energy density of approximately 42.8-43.5 MJ/kg.“Military grade” jet fuel refers to the Jet Propulsion or “JP” numberingsystem (JP-1, JP-2, JP-3, JP-4, JP-5, JP-6, JP-7, JP-8, etc.). Militarygrade jet fuels may comprise alternative or additional additives to havehigher flash points than Jet A, Jet A-1, or Jet B in order to cope withheat and stress endured during supersonic flight.

As used herein, the term “diesel fuel” may refer to a hydrocarboncomposition having the following property characteristics, including acarbon number distribution between about 8 and about 25. Diesel fuelsalso typically have a specific gravity of approximately 0.82-1.08 at15.6° C. (60° F.), based on water having a specific gravity of 1 at 60°F. Diesel fuels typically comprise a distillation range betweenapproximately 180-340° C. (356-644° F.). Additionally, diesel fuels havea minimum cetane index number of approximately 40.

As used herein, the term “carbon number distribution” may refer to therange of compounds present in a composition, wherein each compound isdefined by the number of carbon atoms present. As a non-limitingexample, a naphtha-type jet fuel typically comprises a distribution ofhydrocarbon compounds wherein a majority of those compounds have between5 and 15 carbon atoms each. A kerosene-type jet fuel typically comprisesa distribution of hydrocarbon compounds wherein a majority of thosecompounds have between 8 and 16 carbon atoms each. A diesel fueltypically comprises a distribution of hydrocarbon compounds wherein amajority of those compounds have between 8 and 25 carbon atoms each.

As used herein, the term “energy density” may refer to the amount ofenergy stored in a given system per unit mass (MJ/kg) or per unit volume(MJ/L), where MJ refer to million Joules. As a non-limiting example, theenergy density of kerosene- or naphtha-type jet fuel is typicallygreater than about 40 MJ/kg.

A number of valuable compositions may be targeted through theself-metathesis reaction of a natural oil feedstock, or thecross-metathesis reaction of the natural oil feedstock with alow-molecular-weight olefin, in the presence of a metathesis catalyst.Such valuable compositions may include fuel compositions, non-limitingexamples of which include jet, kerosene, or diesel fuel. Additionally,transesterified products may also be targeted, non-limiting examples ofwhich include: fatty acid methyl esters; biodiesel; 9-decenoic acid(“9DA”) esters, 9-undecenoic acid (“9UDA”) esters, and/or 9-dodecenoicacid (“9DDA”) esters; 9DA, 9UDA, and/or 9DDA; alkali metal salts andalkaline earth metal salts of 9DA, 9UDA, and/or 9DDA; dimers of thetransesterified products; and mixtures thereof.

In certain embodiments, prior to a metathesis reaction, a natural oilfeedstock may be treated to render the natural oil more suitable for thesubsequent metathesis reaction. In certain embodiments, the natural oilpreferably is a vegetable oil or vegetable oil derivative, such assoybean oil.

In one embodiment, the treatment of the natural oil involves the removalof catalyst poisons, such as peroxides, which may potentially diminishthe activity of the metathesis catalyst. Non-limiting examples ofnatural oil feedstock treatment methods to diminish catalyst poisonsinclude those described in PCT/US2008/09604, PCT/US2008/09635, and U.S.patent application Ser. Nos. 12/672,651 and 12/672,652, hereinincorporated by reference in their entireties. In certain embodiments,the natural oil feedstock is thermally treated by heating the feedstockto a temperature greater than 100° C. in the absence of oxygen and heldat the temperature for a time sufficient to diminish catalyst poisons inthe feedstock. In other embodiments, the temperature is betweenapproximately 100° C. and 300° C., between approximately 120° C. and250° C., between approximately 150° C. and 210° C., or approximatelybetween 190 and 200° C. In one embodiment, the absence of oxygen isachieved by sparging the natural oil feedstock with nitrogen, whereinthe nitrogen gas is pumped into the feedstock treatment vessel at apressure of approximately 10 atm (150 psig).

In certain embodiments, the natural oil feedstock is chemically treatedunder conditions sufficient to diminish the catalyst poisons in thefeedstock through a chemical reaction of the catalyst poisons. Incertain embodiments, the feedstock is treated with a reducing agent or acation-inorganic base composition. Non-limiting examples of reducingagents include bisulfate, borohydride, phosphine, thiosulfate,individually or combinations thereof.

In certain embodiments, the natural oil feedstock is treated with anadsorbent to remove catalyst poisons. In one embodiment, the feedstockis treated with a combination of thermal and adsorbent methods. Inanother embodiment, the feedstock is treated with a combination ofchemical and adsorbent methods. In another embodiment, the treatmentinvolves a partial hydrogenation treatment to modify the natural oilfeedstock's reactivity with the metathesis catalyst. Additionalnon-limiting examples of feedstock treatment are also described belowwhen discussing the various metathesis catalysts.

Additionally, in certain embodiments, the low-molecular-weight olefinmay also be treated prior to the metathesis reaction. Like the naturaloil treatment, the low-molecular-weight olefin may be treated to removepoisons that may impact or diminish catalyst activity.

As shown in FIG. 1, after this optional treatment of the natural oilfeedstock and/or low-molecular-weight olefin, the natural oil 12 isreacted with itself, or combined with a low-molecular-weight olefin 14in a metathesis reactor 20 in the presence of a metathesis catalyst.Metathesis catalysts and metathesis reaction conditions are discussed ingreater detail below. In certain embodiments, in the presence of ametathesis catalyst, the natural oil 12 undergoes a self-metathesisreaction with itself. In other embodiments, in the presence of themetathesis catalyst, the natural oil 12 undergoes a cross-metathesisreaction with the low-molecular-weight olefin 14. In certainembodiments, the natural oil 12 undergoes both self- andcross-metathesis reactions in parallel metathesis reactors. Theself-metathesis and/or cross-metathesis reaction form a metathesizedproduct 22 wherein the metathesized product 22 comprises olefins 32 andesters 34.

In certain embodiments, the low-molecular-weight olefin 14 is in the C₂to C₆ range. As a non-limiting example, in one embodiment, thelow-molecular-weight olefin 14 may comprise at least one of thefollowing: ethylene, propylene, 1-butene, 2-butene, isobutene,1-pentene, 2-pentene, 3-pentene, 2-methyl-1-butene, 2-methyl-2-butene,3-methyl-1-butene, cyclopentene, 1-hexene, 2-hexene, 3-hexene, 4-hexene,2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene,2-methyl-2-pentene, 3-methyl-2-pentene, 4-methyl-2-pentene,2-methyl-3-pentene, and cyclohexene. In another embodiment, thelow-molecular-weight olefin 14 comprises at least one of styrene andvinyl cyclohexane. In another embodiment, the low-molecular-weightolefin 14 may comprise at least one of ethylene, propylene, 1-butene,2-butene, and isobutene. In another embodiment, the low-molecular-weightolefin 14 comprises at least one alpha-olefin or terminal olefin in theC₂ to C₁₀ range.

In another embodiment, the low-molecular-weight olefin 14 comprises atleast one branched low-molecular-weight olefin in the C₄ to C₁₀ range.Non-limiting examples of branched low-molecular-weight olefins includeisobutene, 3-methyl-1-butene, 2-methyl-3-pentene, and2,2-dimethyl-3-pentene. By using these branched low-molecular-weightolefins in the metathesis reaction, the methathesized product willinclude branched olefins, which can be subsequently hydrogenated toiso-paraffins. In certain embodiments, the branched low-molecular-weightolefins may help achieve the desired performance properties for a fuelcomposition, such as jet, kerosene, or diesel fuel.

As noted, it is possible to use a mixture of various linear or branchedlow-molecular-weight olefins in the reaction to achieve the desiredmetathesis product distribution. In one embodiment, a mixture of butenes(1-butene, 2-butenes, and, optionally, isobutene) may be employed as thelow-molecular-weight olefin, offering a low cost, commercially availablefeedstock instead a purified source of one particular butene. Such lowcost mixed butene feedstocks are typically diluted with n-butane and/orisobutane.

In certain embodiments, recycled streams from downstream separationunits may be introduced to the metathesis reactor 20 in addition to thenatural oil 12 and, in some embodiments, the low-molecular-weight olefin14. For instance, in some embodiments, a C₂-C₆ recycle olefin stream ora C₃-C₄ bottoms stream from an overhead separation unit may be returnedto the metathesis reactor. In one embodiment, as shown in FIG. 1, alight weight olefin stream 44 from an olefin separation unit 40 may bereturned to the metathesis reactor 20. In another embodiment, the C₃-C₄bottoms stream and the light weight olefin stream 44 are combinedtogether and returned to the metathesis reactor 20. In anotherembodiment, a C₁₅₊ bottoms stream 46 from the olefin separation unit 40is returned to the metathesis reactor 20. In another embodiment, all ofthe aforementioned recycle streams are returned to the metathesisreactor 20.

The metathesis reaction in the metathesis reactor 20 produces ametathesized product 22. In one embodiment, the metathesized product 22enters a flash vessel operated under temperature and pressure conditionswhich target C₂ or C₂-C₃ compounds to flash off and be removed overhead.The C₂ or C₂-C₃ light ends are comprised of a majority of hydrocarboncompounds having a carbon number of 2 or 3. In certain embodiments, theC₂ or C₂-C₃ light ends are then sent to an overhead separation unit,wherein the C₂ or C₂-C₃ compounds are further separated overhead fromthe heavier compounds that flashed off with the C₂-C₃ compounds. Theseheavier compounds are typically C₃-C₅ compounds carried overhead withthe C₂ or C₂-C₃ compounds. After separation in the overhead separationunit, the overhead C₂ or C₂-C₃ stream may then be used as a fuel source.These hydrocarbons have their own value outside the scope of a fuelcomposition, and may be used or separated at this stage for other valuedcompositions and applications. In certain embodiments, the bottomsstream from the overhead separation unit containing mostly C₃-C₅compounds is returned as a recycle stream to the metathesis reactor. Inthe flash vessel, the metathesized product 22 that does not flashoverhead is sent downstream for separation in a separation unit 30, suchas a distillation column.

Prior to the separation unit 30, in certain embodiments, themetathesized product 22 may be introduced to an adsorbent bed tofacilitate the separation of the metathesized product 22 from themetathesis catalyst. In one embodiment, the adsorbent is a clay bed. Theclay bed will adsorb the metathesis catalyst, and after a filtrationstep, the metathesized product 22 can be sent to the separation unit 30for further processing. In another embodiment, the adsorbent is a watersoluble phosphine reagent such as tris hydroxymethyl phosphine (THMP).Catalyst may be separated with a water soluble phosphine through knownliquid-liquid extraction mechanisms by decanting the aqueous phase fromthe organic phase. In other embodiments, the metathesized product 22 maybe contacted with a reactant to deactivate or to extract the catalyst.

In the separation unit 30, in certain embodiments, the metathesizedproduct 22 is separated into at least two product streams. In oneembodiment, the metathesized product 22 is sent to the separation unit30, or distillation column, to separate the olefins 32 from the esters34. In another embodiment, a byproduct stream comprising C₇'s andcyclohexadiene may be removed in a side-stream from the separation unit30. In certain embodiments, the separated olefins 32 may comprisehydrocarbons with carbon numbers up to 24. In certain embodiments, theesters 34 may comprise metathesized glycerides. In other words, thelighter end olefins 32 are preferably separated or distilled overheadfor processing into olefin compositions, while the esters 34, comprisedmostly of compounds having carboxylic acid/ester functionality, aredrawn into a bottoms stream. Based on the quality of the separation, itis possible for some ester compounds to be carried into the overheadolefin stream 32, and it is also possible for some heavier olefinhydrocarbons to be carried into the ester stream 34.

In one embodiment, the olefins 32 may be collected and sold for anynumber of known uses. In other embodiments, the olefins 32 are furtherprocessed in an olefin separation unit 40 and/or hydrogenation unit 50(where the olefinic bonds are saturated with hydrogen gas 48, asdescribed below). In other embodiments, esters 34 comprising heavier endglycerides and free fatty acids are separated or distilled as a bottomsproduct for further processing into various products. In certainembodiments, further processing may target the production of thefollowing non-limiting examples: fatty acid methyl esters; biodiesel;9DA esters, 9UDA esters, and/or 9DDA esters; 9DA, 9UDA, and/or 9DDA;alkali metal salts and alkaline earth metal salts of 9DA, 9UDA, and/or9DDA; diacids, and/or diesters of the transesterified products; andmixtures thereof. In certain embodiments, further processing may targetthe production of C₁₅-C₁₈ fatty acids and/or esters. In otherembodiments, further processing may target the production of diacidsand/or diesters. In yet other embodiments, further processing may targetthe production of compounds having molecular weights greater than themolecular weights of stearic acid and/or linolenic acid.

As shown in FIG. 1, regarding the overhead olefins 32 from theseparation unit 30, the olefins 32 may be further separated or distilledin the olefin separation unit 40 to separate the stream's variouscomponents. In one embodiment, light end olefins 44 consisting of mainlyC₂-C₉ compounds may be distilled into an overhead stream from the olefinseparation unit 40. In certain embodiments, the light end olefins 44 arecomprised of a majority of C₃-C₈ hydrocarbon compounds. In otherembodiments, heavier olefins having higher carbon numbers may beseparated overhead into the light end olefin stream 44 to assist intargeting a specific fuel composition. The light end olefins 44 may berecycled to the metathesis reactor 20, purged from the system forfurther processing and sold, or a combination of the two. In oneembodiment, the light end olefins 44 may be partially purged from thesystem and partially recycled to the metathesis reactor 20. With regardsto the other streams in the olefin separation unit 40, a heavier C₁₆₊,C₁₈₊, C₂₀₊, C₂₂₊, or C₂₄₊ compound stream may be separated out as anolefin bottoms stream 46. This olefin bottoms stream 46 may be purged orrecycled to the metathesis reactor 20 for further processing, or acombination of the two. In another embodiment, a center-cut olefinstream 42 may be separated out of the olefin distillation unit forfurther processing. The center-cut olefins 42 may be designed to targeta selected carbon number range for a specific fuel composition. As anon-limiting example, a C₅-C₁₅ distribution may be targeted for furtherprocessing into a naphtha-type jet fuel. Alternatively, a C₈-C₁₆distribution may be targeted for further processing into a kerosene-typejet fuel. In another embodiment, a C₈-C₂₅ distribution may be targetedfor further processing into a diesel fuel.

In certain embodiments, the olefins 32 may be oligomerized to formpoly-alpha-olefins (PAOs) or poly-internal-olefins (PIOs), mineral oilsubstitutes, and/or biodiesel fuel. The oligomerization reaction maytake place after the distillation unit 30 or after the overhead olefinseparation unit 40. In certain embodiments, byproducts from theoligomerization reactions may be recycled back to the metathesis reactor20 for further processing.

As mentioned, in one embodiment, the olefins 32 from the separation unit30 may be sent directly to the hydrogenation unit 50. In anotherembodiment, the center-cut olefins 42 from the overhead olefinseparation unit 40 may be sent to the hydrogenation unit 50.Hydrogenation may be conducted according to any known method in the artfor hydrogenating double bond-containing compounds such as the olefins32 or center-cut olefins 42. In certain embodiments, in thehydrogenation unit 50, hydrogen gas 48 is reacted with the olefins 32 orcenter-cut olefins 42 in the presence of a hydrogenation catalyst toproduce a hydrogenated product 52.

In some embodiments, the olefins are hydrogenated in the presence of ahydrogenation catalyst comprising nickel, copper, palladium, platinum,molybdenum, iron, ruthenium, osmium, rhodium, or iridium, individuallyor in combinations thereof. Useful catalyst may be heterogeneous orhomogeneous. In some embodiments, the catalysts are supported nickel orsponge nickel type catalysts.

In some embodiments, the hydrogenation catalyst comprises nickel thathas been chemically reduced with hydrogen to an active state (i.e.,reduced nickel) provided on a support. The support may comprise poroussilica (e.g., kieselguhr, infusorial, diatomaceous, or siliceous earth)or alumina. The catalysts are characterized by a high nickel surfacearea per gram of nickel.

Commercial examples of supported nickel hydrogenation catalysts includethose available under the trade designations “NYSOFACT”, “NYSOSEL”, and“NI 5248 D” (from BASF Catalysts LLC, Iselin, N.J.). Additionalsupported nickel hydrogenation catalysts include those commerciallyavailable under the trade designations “PRICAT 9910”, “PRICAT 9920”,“PRICAT 9908”, “PRICAT 9936” (from Johnson Matthey Catalysts, Ward Hill,Mass.).

The supported nickel catalysts may be of the type described in U.S. Pat.No. 3,351,566, U.S. Pat. No. 6,846,772, EP 0168091, and EP 0167201,incorporated by reference herein in their entireties. Hydrogenation maybe carried out in a batch or in a continuous process and may be partialhydrogenation or complete hydrogenation. In certain embodiments, thetemperature ranges from about 50° C. to about 350° C., about 100° C. toabout 300° C., about 150° C. to about 250° C., or about 100° C. to about150° C. The desired temperature may vary, for example, with hydrogen gaspressure. Typically, a higher gas pressure will require a lowertemperature. Hydrogen gas is pumped into the reaction vessel to achievea desired pressure of H₂ gas. In certain embodiments, the H₂ gaspressure ranges from about 15 psig (1 atm) to about 3000 psig (204.1atm), about 15 psig (1 atm) to about 90 psig (6.1 atm), or about 100psig (6.8 atm) to about 500 psig (34 atm). As the gas pressureincreases, more specialized high-pressure processing equipment may berequired. In certain embodiments, the reaction conditions are “mild,”wherein the temperature is approximately between approximately 50° C.and approximately 100° C. and the H₂ gas pressure is less thanapproximately 100 psig. In other embodiments, the temperature is betweenabout 100° C. and about 150° C., and the pressure is between about 100psig (6.8 atm) and about 500 psig (34 atm). When the desired degree ofhydrogenation is reached, the reaction mass is cooled to the desiredfiltration temperature.

The amount of hydrogenation catalyst is typically selected in view of anumber of factors including, for example, the type of hydrogenationcatalyst used, the amount of hydrogenation catalyst used, the degree ofunsaturation in the material to be hydrogenated, the desired rate ofhydrogenation, the desired degree of hydrogenation (e.g., as measure byiodine value (IV)), the purity of the reagent, and the H₂ gas pressure.In some embodiments, the hydrogenation catalyst is used in an amount ofabout 10 weight % or less, for example, about 5 weight % or less orabout 1 weight % or less.

During hydrogenation, the carbon-carbon double bond containing compoundsin the olefins are partially to fully saturated by the hydrogen gas 48.In one embodiment, the resulting hydrogenated product 52 includeshydrocarbons with a distribution centered between approximately C₁₀ andC₁₂ hydrocarbons for naphtha- and kerosene-type jet fuel compositions.In another embodiment, the distribution is centered betweenapproximately C₁₆ and C₁₈ for a diesel fuel composition.

In certain embodiments, after hydrogenation, the hydrogenation catalystmay be removed from the hydrogenated product 52 using known techniquesin the art, for example, by filtration. In some embodiments, thehydrogenation catalyst is removed using a plate and frame filter such asthose commercially available from Sparkler Filters, Inc., Conroe Tex. Insome embodiments, the filtration is performed with the assistance ofpressure or a vacuum. In order to improve filtering performance, afilter aid may be used. A filter aid may be added to the productdirectly or it may be applied to the filter. Representative non-limitingexamples of filtering aids include diatomaceous earth, silica, alumina,and carbon. Typically, the filtering aid is used in an amount of about10 weight % or less, for example, about 5 weight % or less or about 1weight % or less. Other filtering techniques and filtering aids also maybe employed to remove the used hydrogenation catalyst. In otherembodiments the hydrogenation catalyst is removed using centrifugationfollowed by decantation of the product.

In certain embodiments, based upon the quality of the hydrogenatedproduct 52 produced in the hydrogenation unit 50, it may be preferableto isomerize the olefin hydrogenated product 52 to assist in targetingof desired fuel properties such as flash point, freeze point, energydensity, cetane number, or end point distillation temperature, amongother parameters. Isomerization reactions are well-known in the art, asdescribed in U.S. Pat. Nos. 3,150,205; 4,210,771; 5,095,169; and6,214,764, herein incorporated by reference in their entireities. In oneembodiment, the isomerization reaction at this stage may also crack someof the C₁₅₊ compounds remaining, which may further assist in producing afuel composition having compounds within the desired carbon numberrange, such as 5 to 16 for a jet fuel composition.

In certain embodiments, the isomerization may occur concurrently withthe hydrogenation step in the hydrogenation unit 50, thereby targeting adesired fuel product. In other embodiments, the isomerization step mayoccur before the hydrogenation step (i.e., the olefins 32 or center-cutolefins 42 may be isomerized before the hydrogenation unit 50). In yetother embodiments, it is possible that the isomerization step may beavoided or reduced in scope based upon the selection oflow-molecular-weight olefin(s) 14 used in the metathesis reaction.

In certain embodiments, the hydrogenated product 52 comprisesapproximately 15-25 weight % C₇, approximately <5 weight % C₈,approximately 20-40 weight % C₉, approximately 20-40 weight % C₁₀,approximately <5 weight % C₁₁, approximately 15-25 weight % C₁₂,approximately <5 weight % C₁₃, approximately <5 weight % C₁₄,approximately <5 weight % C₁₅, approximately <1 weight % C₁₆,approximately <1 weight % C₁₇, and approximately <1 weight % C₁₈+. Incertain embodiments, the hydrogenated product 52 comprises a heat ofcombustion of at least approximately 40, 41, 42, 43 or 44 MJ/kg (asmeasured by ASTM D3338). In certain embodiments, the hydrogenatedproduct 52 contains less than approximately 1 mg sulfur per kghydrogenated product (as measured by ASTM D5453). In other embodiments,the hydrogenated product 52 comprises a density of approximately0.70-0.75 (as measured by ASTM D4052). In other embodiments, thehydrogenated product has a final boiling point of approximately 220-240°C. (as measured by ASTM D86).

The hydrogenated product 52 produced from the hydrogenation unit 50 maybe used as a fuel composition, non-limiting examples of which includejet, kerosene, or diesel fuel. In certain embodiments, the hydrogenatedproduct 52 may contain byproducts from the hydrogenation, isomerization,and/or metathesis reactions. As shown in FIG. 1, the hydrogenatedproduct 52 may be further processed in a fuel composition separationunit 60, removing any remaining byproducts from the hydrogenated product52, such as hydrogen gas, water, C₂-C₉ hydrocarbons, or C₁₅+hydrocarbons, thereby producing a targeted fuel composition. In oneembodiment, the hydrogenated product 52 may be separated into thedesired fuel C₉-C₁₅ product 64, and a light-ends C₂-C₉ fraction 62and/or a C₁₅+ heavy-ends fraction 66. Distillation may be used toseparate the fractions. Alternatively, in other embodiments, such as fora naphtha- or kerosene-type jet fuel composition, the heavy endsfraction 66 can be separated from the desired fuel product 64 by coolingthe hydrogenated product 52 to approximately −40° C., −47° C., or −65°C. and then removing the solid, heavy ends fraction 66 by techniquesknown in the art such as filtration, decantation, or centrifugation.

With regard to the esters 34 from the distillation unit 30, in certainembodiments, the esters 34 may be entirely withdrawn as an ester productstream 36 and processed further or sold for its own value, as shown inFIG. 1. As a non-limiting example, the esters 34 may comprise varioustriglycerides that could be used as a lubricant. Based upon the qualityof separation between olefins and esters, the esters 34 may comprisesome heavier olefin components carried with the triglycerides. In otherembodiments, the esters 34 may be further processed in a biorefinery oranother chemical or fuel processing unit known in the art, therebyproducing various products such as biodiesel or specialty chemicals thathave higher value than that of the triglycerides, for example.Alternatively, in certain embodiments, the esters 34 may be partiallywithdrawn from the system and sold, with the remainder further processedin the biorefinery or another chemical or fuel processing unit known inthe art.

In certain embodiments, the ester stream 34 is sent to atransesterification unit 70. Within the transesterification unit 70, theesters 34 are reacted with at least one alcohol 38 in the presence of atransesterification catalyst. In certain embodiments, the alcoholcomprises methanol and/or ethanol. In one embodiment, thetransesterification reaction is conducted at approximately 60-70° C. andapproximately 1 atm. In certain embodiments, the transesterificationcatalyst is a homogeneous sodium methoxide catalyst. Varying amounts ofcatalyst may be used in the reaction, and, in certain embodiments, thetransesterification catalyst is present in the amount of approximately0.5-1.0 weight % of the esters 34.

The transesterification reaction may produce transesterified products 72including saturated and/or unsaturated fatty acid methyl esters(“FAME”), glycerin, methanol, and/or free fatty acids. In certainembodiments, the transesterified products 72, or a fraction thereof, maycomprise a source for biodiesel. In certain embodiments, thetransesterified products 72 comprise 9DA esters, 9UDA esters, and/or9DDA esters. Non-limiting examples of 9DA esters, 9UDA esters and 9DDAesters include methyl 9-decenoate (“9-DAME”), methyl 9-undecenoate(“9-UDAME”), and methyl 9-dodecenoate (“9-DDAME”), respectively. As anon-limiting example, in a transesterification reaction, a 9DA moiety ofa metathesized glyceride is removed from the glycerol backbone to form a9DA ester.

In another embodiment, a glycerin alcohol may be used in the reactionwith a glyceride stream. This reaction may produce monoglycerides and/ordiglycerides.

In certain embodiments, the transesterified products 72 from thetransesterification unit 70 can be sent to a liquid-liquid separationunit, wherein the transesterified products 72 (i.e., FAME, free fattyacids, and/or alcohols) are separated from glycerin. Additionally, incertain embodiments, the glycerin byproduct stream may be furtherprocessed in a secondary separation unit, wherein the glycerin isremoved and any remaining alcohols are recycled back to thetransesterification unit 70 for further processing.

In one embodiment, the transesterified products 72 are further processedin a water-washing unit. In this unit, the transesterified productsundergo a liquid-liquid extraction when washed with water. Excessalcohol, water, and glycerin are removed from the transesterifiedproducts 72. In another embodiment, the water-washing step is followedby a drying unit in which excess water is further removed from thedesired mixture of esters (i.e., specialty chemicals). Such specialtychemicals include non-limiting examples such as 9DA, 9UDA, and/or 9DDA,alkali metal salts and alkaline earth metal salts of the preceding,individually or in combinations thereof.

In one embodiment, the specialty chemical (e.g., 9DA) may be furtherprocessed in an oligomerization reaction to form a lactone, which mayserve as a precursor to a surfactant.

In certain embodiments, the transesterifed products 72 from thetransesterification unit 70 or specialty chemicals from thewater-washing unit or drying unit are sent to an ester distillationcolumn 80 for further separation of various individual or groups ofcompounds, as shown in FIG. 1. This separation may include, but is notlimited to, the separation of 9DA esters, 9UDA esters, and/or 9DDAesters. In one embodiment, the 9DA ester 82 may be distilled orindividually separated from the remaining mixture 84 of transesterifiedproducts or specialty chemicals. In certain process conditions, the 9DAester 82 should be the lightest component in the transesterified productor specialty chemical stream, and come out at the top of the esterdistillation column 80. In another embodiment, the remaining mixture 84,or heavier components, of the transesterified products or specialtychemicals may be separated off the bottom end of the column. In certainembodiments, this bottoms stream 84 may potentially be sold asbiodiesel.

The 9DA esters, 9UDA esters, and/or 9DDA esters may be further processedafter the distillation step in the ester distillation column. In oneembodiment, under known operating conditions, the 9DA ester, 9UDA ester,and/or 9DDA ester may then undergo a hydrolysis reaction with water toform 9DA, 9UDA, and/or 9DDA, alkali metal salts and alkaline earth metalsalts of the preceding, individually or in combinations thereof.

In certain embodiments, the fatty acid methyl esters from thetransesterified products 72 may be reacted with each other to form otherspecialty chemicals such as dimers.

FIG. 2 represents another embodiment for processing the natural oil intofuel compositions and specialty chemicals. As described above, thenatural oil feedstock and/or low-molecular-weight olefin in FIG. 2 mayundergo a pretreatment step prior to the metathesis reaction. In FIG. 2,the natural oil feedstock 112 is reacted with itself, or combined with alow-molecular-weight olefin 114 in a metathesis reactor 120 in thepresence of a metathesis catalyst. In certain embodiments, in thepresence of a metathesis catalyst, the natural oil 112 undergoes aself-metathesis reaction with itself. In other embodiments, in thepresence of the metathesis catalyst, the natural oil 112 undergoes across-metathesis reaction with the low-molecular-weight olefin 114. Incertain embodiments, the natural oil 112 undergoes both self- andcross-metathesis reactions in parallel metathesis reactors. Theself-metathesis and/or cross-metathesis reaction form a metathesizedproduct 122 wherein the metathesized product 122 comprises olefins 132and esters 134.

In certain embodiments, the low-molecular-weight olefin 114 is in the C₂to C₆ range. As a non-limiting example, in one embodiment, thelow-molecular-weight olefin 114 may comprise at least one of thefollowing: ethylene, propylene, 1-butene, 2-butene, isobutene,1-pentene, 2-pentene, 3-pentene, 2-methyl-1-butene, 2-methyl-2-butene,3-methyl-1-butene, cyclopentene, 1-hexene, 2-hexene, 3-hexene, 4-hexene,2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene,2-methyl-2-pentene, 3-methyl-2-pentene, 4-methyl-2-pentene,2-methyl-3-pentene, and cyclohexene. In another embodiment, thelow-molecular-weight olefin 114 comprises at least one of styrene andvinyl cyclohexane. In another embodiment, the low-molecular-weightolefin 114 may comprise at least one of ethylene, propylene, 1-butene,2-butene, and isobutene. In another embodiment, the low-molecular-weightolefin 114 comprises at least one alpha-olefin or terminal olefin in theC₂ to C₁₀ range.

In another embodiment, the low-molecular-weight olefin 114 comprises atleast one branched low-molecular-weight olefin in the C₄ to C₁₀ range.Non-limiting examples of branched low-molecular-weight olefins includeisobutene, 3-methyl-1-butene, 2-methyl-3-pentene, and2,2-dimethyl-3-pentene. In certain embodiments, the branchedlow-molecular-weight olefins may help achieve the desired performanceproperties for the fuel composition, such as jet, kerosene, or dieselfuel.

As noted, it is possible to use a mixture of various linear or branchedlow-molecular-weight olefins in the reaction to achieve the desiredmetathesis product distribution. In one embodiment, a mixture of butenes(1-butene, 2-butene, and isobutene) may be employed as thelow-molecular-weight olefin 114.

In certain embodiments, recycled streams from downstream separationunits may be introduced to the metathesis reactor 120 in addition to thenatural oil 112 and, in some embodiments, the low-molecular-weightolefin 114 to improve the yield of the targeted fuel composition and/ortargeted transesterification products.

After the metathesis unit 120 and before the hydrogenation unit 125, incertain embodiments, the metathesized product 122 may be introduced toan adsorbent bed to facilitate the separation of the metathesizedproduct 122 from the metathesis catalyst. In one embodiment, theadsorbent is a clay. The clay will adsorb the metathesis catalyst, andafter a filtration step, the metathesized product 122 can be sent to thehydrogenation unit 125 for further processing. In another embodiment,the adsorbent is a water soluble phosphine reagent such as trishydroxymethyl phosphine (THMP). Catalyst may be separated from thereaction mixture with a water soluble phosphine through knownliquid-liquid extraction mechanisms by decanting the aqueous phase fromthe organic phase. In other embodiments, addition of a reactant todeactivate or extract the catalyst might be used.

As shown in FIG. 2, the metathesis product 122 is sent to ahydrogenation unit 125, wherein the carbon-carbon double bonds in theolefins and esters are partially to fully saturated with hydrogen gas124. As described above, hydrogenation may be conducted according to anyknown method in the art for hydrogenating double bond-containingcompounds such as the olefins and esters present in the metathesisproduct 122. In certain embodiments, in the hydrogenation unit 125,hydrogen gas 124 is reacted with the metathesis product 122 in thepresence of a hydrogenation catalyst to produce a hydrogenated product126 comprising partially to fully hydrogenated paraffins/olefins andpartially to fully hydrogenated esters.

Typical hydrogenation catalysts have been already described withreference to embodiments in FIG. 1. Reaction conditions have also beendescribed. In certain embodiments, the temperature ranges from about 50°C. to about 350° C., about 100° C. to about 300° C., about 150° C. toabout 250° C., or about 50° C. to about 150° C. The desired temperaturemay vary, for example, with hydrogen gas pressure. Typically, a highergas pressure might allow the use of a lower reaction temperature.Hydrogen gas is pumped into the reaction vessel to achieve a desiredpressure of H₂ gas. In certain embodiments, the H₂ gas pressure rangesfrom about 15 psig (1 atm) to about 3000 psig (204.1 atm), or about 15psig (1 atm) to about 500 psig (34 atm). In certain embodiments, thereaction conditions are “mild,” wherein the temperature is approximatelybetween approximately 50° C. and approximately 150° C. and the H₂ gaspressure is less than approximately 400 psig. When the desired degree ofhydrogenation is reached, the reaction mass is cooled to the desiredfiltration temperature.

During hydrogenation, the carbon-carbon double bonds are partially tofully saturated by the hydrogen gas 124. In one embodiment, the olefinsin the metathesis product 122 are reacted with hydrogen to form a fuelcomposition comprising only or mostly paraffins. Additionally, theesters from the metathesis product are fully or nearly fully saturatedin the hydrogenation unit 125. In another embodiment, the resultinghydrogenated product 126 includes only partially saturatedparaffins/olefins and partially saturated esters.

In FIG. 2, the hydrogenated product 126 is sent to a separation unit 130to separate the product into at least two product streams. In oneembodiment, the hydrogenated product 126 is sent to the separation unit130, or distillation column, to separate the partially to fullysaturated paraffins/olefins, or fuel composition 132, from the partiallyto fully saturated esters 134. In another embodiment, a byproduct streamcomprising C₇'s and cyclohexadiene may be removed in a side-stream fromthe separation unit 130. In certain embodiments, the fuel composition132 may comprise hydrocarbons with carbon numbers up to 24. In oneembodiment, the fuel composition 132 consists essentially of saturatedhydrocarbons.

In certain embodiments, the esters 134 may comprise metathesized,partially to fully hydrogenated glycerides. In other words, the lighterend paraffins/olefins 132 are preferably separated or distilled overheadfor processing into fuel compositions, while the esters 134, comprisedmostly of compounds having carboxylic acid/ester functionality, aredrawn as a bottoms stream. Based on the quality of the separation, it ispossible for some ester compounds to be carried into the overheadparaffin/olefin stream 132, and it is also possible for some heavierparaffin/olefin hydrocarbons to be carried into the ester stream 134.

In certain embodiments, it may be preferable to isomerize the fuelcomposition 132 to improve the quality of the product stream and targetthe desired fuel properties such as flash point, freeze point, energydensity, cetane number, or end point distillation temperature, amongother parameters. Isomerization reactions are well-known in the art, asdescribed in U.S. Pat. Nos. 3,150,205; 4,210,771; 5,095,169; and6,214,764, herein incorporated by reference in their entireties. In oneembodiment, as shown in FIG. 2, the fuel composition 132 is sent to anisomerization reaction unit 150 wherein an isomerized fuel composition152 is produced. Under typical reaction conditions, the isomerizationreaction at this stage may also crack some of the compounds present instream 132, which may further assist in producing an improved fuelcomposition having compounds within the desired carbon number range,such as 5 to 16 for a jet fuel composition.

In certain embodiments, the fuel composition 132 or isomerized fuelcomposition 152 comprises approximately 15-25 weight % C₇, approximately<5 weight % C₈, approximately 20-40 weight % C₉, approximately 20-40weight % C₁₀, approximately <5 weight % C₁₁, approximately 15-25 weight% C₁₂, approximately <5 weight % C₁₃, approximately <5 weight % C₁₄,approximately <5 weight % C₁₅, approximately <1 weight % C₁₆,approximately <1 weight % C₁₇, and approximately <1 weight % C₁₈+. Incertain embodiments, the fuel composition 132 or isomerized fuelcomposition 152 comprises a heat of combustion of at least approximately40, 41, 42, 43 or 44 MJ/kg (as measured by ASTM D3338). In certainembodiments, the fuel composition 132 or isomerized fuel composition 152contains less than approximately 1 mg sulfur per kg fuel composition (asmeasured by ASTM D5453). In other embodiments, the fuel composition 132or isomerized fuel composition 152 comprises a density of approximately0.70-0.75 (as measured by ASTM D4052). In other embodiments, the fuelcomposition 132 or isomerized fuel composition 152 has a final boilingpoint of approximately 220-240° C. (as measured by ASTM D86).

The fuel composition 132 or the isomerized fuel composition 152 may beused as jet, kerosene, or diesel fuel, depending on the fuel'scharacteristics. In certain embodiments, the fuel composition maycontain byproducts from the hydrogenation, isomerization, and/ormetathesis reactions. The fuel composition 132 or isomerized fuelcomposition 152 may be further processed in a fuel compositionseparation unit 160 as shown in FIG. 2. The separation unit 160 may beoperated to remove any remaining byproducts from the mixture, such ashydrogen gas, water, C₂-C₉ hydrocarbons, or C₁₅+ hydrocarbons, therebyproducing a desired fuel product 164. In one embodiment, the mixture maybe separated into the desired fuel C₉-C₁₅ product 164, and a light-endsC₂-C₉ (or C₃-C₈) fraction 162 and/or a C₁₈+ heavy-ends fraction 166.Distillation may be used to separate the fractions. Alternatively, inother embodiments, such as for a naphtha- or kerosene-type jet fuelcomposition, the heavy ends fraction 166 can be separated from thedesired fuel product 164 by cooling the paraffins/olefins toapproximately −40° C., −47° C., or −65° C. and then removing the solid,heavy ends fraction 166 by techniques known in the art such asfiltration, decantation, or centrifugation.

With regard to the partially to fully saturated esters 134 from theseparation unit 130, in certain embodiments, the esters 134 may beentirely withdrawn as a partially to fully hydrogenated ester productstream 136 and processed further or sold for its own value, as shown inFIG. 2. As a non-limiting example, the esters 134 may comprise variouspartially to fully saturated triglycerides that could be used as alubricant. Based upon the quality of separation between theparaffins/olefins (fuel composition 132) and the esters, the esters 134may comprise some heavier paraffin and olefin components carried withthe triglycerides. In other embodiments, the esters 134 may be furtherprocessed in a biorefinery or another chemical or fuel processing unitknown in the art, thereby producing various products such as biodieselor specialty chemicals that have higher value than that of thetriglycerides, for example. Alternatively, the esters 134 may bepartially withdrawn from the system and sold, with the remainder furtherprocessed in the biorefinery or another chemical or fuel processing unitknown in the art.

In certain embodiments, the ester stream 134 is sent to atransesterification unit 170. Within the transesterification unit 170,the esters 134 are reacted with at least one alcohol 138 in the presenceof a transesterification catalyst. In certain embodiments, the alcoholcomprises methanol and/or ethanol. In one embodiment, thetransesterification reaction is conducted at approximately 60-70° C. and1 atm. In certain embodiments, the transesterification catalyst is ahomogeneous sodium methoxide catalyst. Varying amounts of catalyst maybe used in the reaction, and, in certain embodiments, thetransesterification catalyst is present in the amount of approximately0.5-1.0 weight % of the esters 134.

The transesterification reaction may produce transesterified products172 including saturated and/or unsaturated fatty acid methyl esters(“FAME”), glycerin, methanol, and/or free fatty acids. In certainembodiments, the transesterified products 172, or a fraction thereof,may comprise a source for biodiesel. In certain embodiments, thetransesterified products 172 comprise decenoic acid esters, decanoicacid esters, undecenoic acid esters, undecanoic acid esters, dodecenoicacid esters, and/or dodecaonic acid esters. In one embodiment, in atransesterification reaction, a decanoic acid moiety of a metathesizedglyceride is removed from the glycerol backbone to form a decanoic acidester. In another embodiment, a decenoic acid moiety of a metathesizedglyceride is removed from the glycerol backbone to form a decenoic acidester.

In another embodiment, a glycerin alcohol may be used in the reactionwith a triglyceride stream 134. This reaction may produce monoglyceridesand/or diglycerides.

In certain embodiments, the transesterified products 172 from thetransesterification unit 170 can be sent to a liquid-liquid separationunit, wherein the transesterified products 172 (i.e., FAME, free fattyacids, and/or alcohols) are separated from glycerin. Additionally, incertain embodiments, the glycerin byproduct stream may be furtherprocessed in a secondary separation unit, wherein the glycerin isremoved and any remaining alcohols are recycled back to thetransesterification unit 170 for further processing.

In one embodiment, the transesterified products 172 are furtherprocessed in a water-washing unit. In this unit, the transesterifiedproducts undergo a liquid-liquid extraction when washed with water.Excess alcohol, water, and glycerin are removed from the transesterifiedproducts 172. In another embodiment, the water-washing step is followedby a drying unit in which excess water is further removed from thedesired mixture of esters (i.e., specialty chemicals). Such hydrogenatedspecialty chemicals include non-limiting examples such as decenoic acid,decanoic acid, undecenoic acid, undecanoic acid, dodecenoic acid,dodecanoic acid, and mixtures thereof.

As shown in FIG. 2, the transesterifed products 172 from thetransesterification unit 170 or specialty chemicals from thewater-washing unit or drying unit may be sent to an ester distillationcolumn 180 for further separation of various individual or groups ofcompounds. This separation may include, but is not limited to, theseparation of decenoic acid esters, decanoic acid esters, undecenoicacid esters, undecanoic acid esters, dodecenoic acid esters, and/ordodecanoic acid esters. In one embodiment, a decanoic acid ester ordecenoic acid ester 182 may be distilled or individually separated fromthe remaining mixture 184 of transesterified products or specialtychemicals. In certain process conditions, the decanoic acid ester ordecenoic acid ester 182 should be the lightest component in thetransesterified product or specialty chemical stream, and come out atthe top of the ester distillation column 180. In another embodiment, theremaining mixture 184, or heavier components, of the transesterifiedproducts or specialty chemicals may be separated off the bottom end ofthe column. In certain embodiments, this bottoms stream 184 maypotentially be sold as biodiesel.

The decenoic acid esters, decanoic acid esters, undecenoic acid esters,undecanoic acid esters, dodecenoic acid esters, and/or dodecanoic acidesters may be further processed after the distillation step in the esterdistillation column. In one embodiment, under known operatingconditions, the decenoic acid ester, decanoic acid ester, undecenoicacid ester, undecanoic acid ester, dodecenoic acid ester, and/ordodecanoic acid ester may then undergo a hydrolysis reaction with waterto form decenoic acid, decanoic acid, undecenoic acid undecanoic acid,dodecenoic acid, and/or dodecanoic acid.

As noted, the self-metathesis of the natural oil or the cross-metathesisbetween the natural oil and low-molecular-weight olefin occurs in thepresence of a metathesis catalyst. As stated previously, the term“metathesis catalyst” includes any catalyst or catalyst system thatcatalyzes a metathesis reaction. Any known or future-developedmetathesis catalyst may be used, individually or in combination with oneor more additional catalysts. Non-limiting exemplary metathesiscatalysts and process conditions are described in PCT/US2008/009635, pp.18-47, incorporated by reference herein. A number of the metathesiscatalysts as shown are manufactured by Materia, Inc. (Pasadena, Calif.).

The metathesis process can be conducted under any conditions adequate toproduce the desired metathesis products. For example, stoichiometry,atmosphere, solvent, temperature, and pressure can be selected by oneskilled in the art to produce a desired product and to minimizeundesirable byproducts. The metathesis process may be conducted under aninert atmosphere. Similarly, if a reagent is supplied as a gas, an inertgaseous diluent can be used. The inert atmosphere or inert gaseousdiluent typically is an inert gas, meaning that the gas does notinteract with the metathesis catalyst to substantially impede catalysis.For example, particular inert gases are selected from the groupconsisting of helium, neon, argon, nitrogen, individually or incombinations thereof.

In certain embodiments, the metathesis catalyst is dissolved in asolvent prior to conducting the metathesis reaction. In certainembodiments, the solvent chosen may be selected to be substantiallyinert with respect to the metathesis catalyst. For example,substantially inert solvents include, without limitation, aromatichydrocarbons, such as benzene, toluene, xylenes, etc.; halogenatedaromatic hydrocarbons, such as chlorobenzene and dichlorobenzene;aliphatic solvents, including pentane, hexane, heptane, cyclohexane,etc.; and chlorinated alkanes, such as dichloromethane, chloroform,dichloroethane, etc. In one particular embodiment, the solvent comprisestoluene.

The metathesis reaction temperature may be a rate-controlling variablewhere the temperature is selected to provide a desired product at anacceptable rate. In certain embodiments, the metathesis reactiontemperature is greater than about −40° C., greater than about −20° C.,greater than about 0° C., or greater than about 10° C. In certainembodiments, the metathesis reaction temperature is less than about 150°C., or less than about 120° C. In one embodiment, the metathesisreaction temperature is between about 10° C. and about 120° C.

The metathesis reaction can be run under any desired pressure.Typically, it will be desirable to maintain a total pressure that ishigh enough to keep the cross-metathesis reagent in solution. Therefore,as the molecular weight of the cross-metathesis reagent increases, thelower pressure range typically decreases since the boiling point of thecross-metathesis reagent increases. The total pressure may be selectedto be greater than about 0.1 atm (10 kPa), in some embodiments greaterthan about 0.3 atm (30 kPa), or greater than about 1 atm (100 kPa).Typically, the reaction pressure is no more than about 70 atm (7000kPa), in some embodiments no more than about 30 atm (3000 kPa). Anon-limiting exemplary pressure range for the metathesis reaction isfrom about 1 atm (100 kPa) to about 30 atm (3000 kPa).

While the invention as described may have modifications and alternativeforms, various embodiments thereof have been described in detail. Itshould be understood, however, that the description herein of thesevarious embodiments is not intended to limit the invention, but on thecontrary, the intention is to cover all modifications, equivalents, andalternatives falling within the spirit and scope of the invention asdefined by the claims. Further, while the invention will also bedescribed with reference to the following non-limiting examples, it willbe understood, of course, that the invention is not limited theretosince modifications may be made by those skilled in the art,particularly in light of the foregoing teachings.

EXAMPLES Example 1

A clean, dry, stainless steel jacketed 5-gal. Parr reactor vesselequipped with a dip tube, overhead stirrer, internal cooling/heatedcoils, temperature probe, sampling valve, and headspace gas releasevalve was purged with argon to 15 psig. Soybean oil (SBO, 2.5 kg, 2.9mol, Costco, MWn=864.4 g/mol, 85 weight % unsaturation as determined byGC, 1 hour argon sparged in 5-gal container) was added into the Parrreactor. The Parr reactor was sealed and the SBO was purged with argonfor 2 hours while cooling to 10° C. After 2 hours, the reactor wasvented until the internal pressure reached 10 psig. The dip tube valveon the reactor was connected to a 1-butene cylinder (Airgas, CP grade,33 psig headspace pressure, >99 weight %) and re-pressurized to 15 psigof 1-butene. The reactor was vented again to 10 psig to remove residualargon in the headspace. The SBO was stirred at 350 rpm and 9-15° C.under 18-28 psig 1-butene until 3 mol 1-butene per SBO olefin bond wastransferred into the reactor (approximately 2.2 kg 1-butene overapproximately 4-5 hours). A toluene solution of[1,3-Bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichlororuthenium(3-methyl-2-butenylidene)(tricyclohexylphosphine)(C827, Materia) was prepared in Fischer-Porter pressure vessel bydissolving 130 mg catalyst in 30 grams of toluene as a catalyst carrier(10 mol ppm per olefin bond of SBO) and was added to the reactor via thereactor dip tube by pressurizing the headspace inside the Fischer-Portervessel to 50-60 psig with argon. The Fischer-Porter vessel and dip tubewere rinsed with an additional 30 g toluene. The reaction mixture wasstirred for 2.0 hours at 60° C. The reaction mixture was allowed to coolto ambient temperature while the gases in the headspace were vented.After the pressure was released, the reaction mixture was transferred toa 3-neck round bottom flask containing 58 g bleaching clay (2% w/w SBO,Pure Flow B80 CG) and a magnetic stir bar. The reaction mixture wastreated by stirring at 85° C. under argon. After 2 hours, during whichtime any remaining 1-butene was allowed to vent, the reaction mixturewas allowed to cool to 40° C. and filtered through a fritted glassfilter. An aliquot of the product mixture was found by gaschromatographic analysis (following transesterification with 1% w/wNaOMe in methanol at 60° C.) to contain approximately 22 weight % methyl9-decenoate, approximately 16 weight % methyl 9-dodecenoate,approximately 3 weight % dimethyl 9-octadecenedioate, and approximately3 weight % methyl 9-octadecenoate (by gc). These results comparefavorably with the calculated yields at equilibrium of 23.4 wt % methyl9-decenoate, 17.9 wt % methyl 9-dodecenoate, 3.7 wt % dimethyl9-octadecenedioate, and 1.8 wt % methyl 9-octadecenoate.

Example 2

By the general procedures described in example 1, a reaction wasperformed using 1.73 kg SBO and 3 mol 1-butene/SBO double bond. Analiquot of the product mixture was found by gas chromatographic analysisfollowing transesterification with 1% w/w NaOMe in methanol at 60° C. tocontain approximately 24 weight % methyl 9-decenoate, approximately 18weight % methyl 9-dodecenoate, approximately 2 weight % dimethyl9-octadecenedioate, and approximately 2 weight % methyl 9-octadecenoate(as determined by gc).

Example 3

By the general procedures described in example 1, a reaction wasperformed using 1.75 kg SBO and 3 mol 1-butene/SBO double bond. Analiquot of the product mixture was found by gas chromatographic analysisfollowing transesterification with 1% w/w NaOMe in methanol at 60° C. tocontain approximately 24 weight % methyl 9-decenoate, approximately 17weight % methyl 9-dodecenoate, approximately 3 weight % dimethyl9-octadecenedioate, and approximately 2 weight % methyl 9-octadecenoate(as determined by gc).

Example 4

By the general procedures described in example 1, a reaction wasperformed using 2.2 kg SBO, 3 mol 1-butene/SBO double bond, and the 60 gof toluene used to transfer the catalyst was replaced with SBO. Analiquot of the product mixture was found by gas chromatographic analysisfollowing transesterification with 1% w/w NaOMe in methanol at 60° C. tocontain approximately 25 weight % methyl 9-decenoate, approximately 18weight % methyl 9-dodecenoate, approximately 3 weight % dimethyl9-octadecenedioate, and approximately 1 weight % methyl 9-octadecenoate(as determined by gc).

Example 5

A 12-liter, 3-neck, glass round bottom flask that was equipped with amagnetic stir bar, heating mantle, and temperature controller wascharged with 8.42 kg of the combined reaction products from examples1-4. A cooling condenser with a vacuum inlet was attached to the middleneck of the flask and a receiving flask was connected to the condenser.Hydrocarbon olefins were removed from the reaction product by vacuumdistillation over the follow range of conditions: 22-130° C. pottemperature, 19-70° C. distillation head temperature, and 2000-160 μtorrpressure. The weight of material remaining after the volatilehydrocarbons were removed was 5.34 kg. An aliquot of the non-volatileproduct mixture was found by gas chromatographic analysis followingtransesterification with 1% w/w NaOMe in methanol at 60° C. to containapproximately 32 weight % methyl 9-decenoate, approximately 23 weight %methyl 9-dodecenoate, approximately 4 weight % dimethyl9-octadecenedioate, and approximately 5 weight % methyl 9-octadecenoate(as determined by gc).

Example 6

A 12-liter, 3-neck round bottom flask that was fitted with a magneticstir bar, condenser, heating mantle, temperature probe, and gas adapterwas charged with 4 liters of 1% w/w NaOMe in MeOH and 5.34 kg of thenon-volatile product mixture produced in example 5. The resulting lightyellow heterogeneous mixture was stirred at 60° C. After about an hour,the mixture turned a homogeneous orange color (detected pH=11.) After atotal reaction time of 2 hours, the mixture was cooled to ambienttemperature and two layers were observed. The organic phase was washedtwice with 3 L of 50% (v/v) aqueous MeOH, separated, and neutralized bywashing with glacial HOAc in MeOH (1 mol HOAc/mol NaOMe) to a detectedpH of 6.5, yielding 5.03 kg.

Example 7

A glass, 12 L, 3-neck round bottom flask fitted with a magnetic stirrer,packed column, and temperature controller was charged with the methylester mixture (5.03 kg) produced in example 6 and placed in the heatingmantle. The column attached to the flask was a 2-inch×36-inch glasscolumn containing 0.16″ Pro-Pak™ stainless steel saddles. Thedistillation column was attached to a fractional distillation head towhich a 1 L pre-weighed round bottom flask was fitted for collecting thedistillation fractions. The distillation was carried out under vacuum at100-120 μtorr. A reflux ratio of 1:3 was used for isolating both methyl9-decenoate (9-DAME) and methyl 9-dodecenoate (9-DDAME). A reflux ratioof 1:3 referred to 1 drop collected for every 3 drops sent back to thedistillation column. The samples collected during the distillation, thevacuum distillation conditions, and the 9-DAME and 9-DDAME content ofthe fractions, as determined by gc, are shown in Table 1. Combiningfractions 2-7 yielded 1.46 kg methyl 9-decenoate with 99.7% purity.After collecting fraction 16, 2.50 kg of material remained in thedistillation pot: it was found by gc to contain approximately 14 weight% 9-DDAME, approximately 42 weight % methyl palmitate, and approximately12 weight % methyl stearate.

TABLE 1 Head Pot 9- 9- Distillation temp. temp. Vacuum Weight DAME DDAMEFractions # (° C.) (° C.) (μtorr) (g) (wt %) (wt %) 1 40-47 104-106 1106.8 80 0 2 45-46 106 110 32.4 99 0 3 47-48 105-110 120 223.6 99 0 449-50 110-112 120 283 99 0 5 50 106 110 555 99 0 6 50 108 110 264 99 0 750 112 110 171 99 0 8 51 114 110 76 97 1 9 65-70 126-128 110 87 47 23 1074 130-131 110 64 0 75 11 75 133 110 52.3 0 74 12 76 135-136 110 38 0 7913 76 136-138 100 52.4 0 90 14 76 138-139 100 25.5 0 85 15 76-77 140 110123 0 98 16 78 140 100 426 0 100

Example 8

A reaction was performed by the general procedures described in example1 with the following changes: 2.2 kg SBO, 7 mol propene/mol SBO doublebond, and 200 mg[1,3-Bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichlororuthenium(benzylidene)(tricyclohexyl-phosphine)[C848 catalyst, Materia Inc., Pasadena, Calif., USA, 90 ppm (w/w) vs.SBO] at a reaction temperature of 40° C. were used. The catalyst removalstep using bleaching clay also was replaced by the following: afterventing excess propene, the reaction mixture was transferred into a3-neck round bottom flask to which tris(hydroxymethyl)phosphine (THMP,1.0 M in isopropanol, 50 mol THMP/mol C848) was added. The resultinghazy yellow mixture was stirred for 20 hours at 60° C., transferred to a6-L separatory funnel and extracted with 2×2.5 L deionized H₂O. Theorganic layer was separated and dried over anhydrous Na₂SO₄ for 4 hours,then filtered through a fritted glass filter containing a bed of silicagel.

Example 9

A reaction was performed by the general procedures described in example8, except that 3.6 kg SBO and 320 mg C848 catalyst were used. Followingcatalyst removal, the reaction product from example 9 was combined withthat from example 8, yielding 5.12 kg of material. An aliquot of thecombined product mixture was found by gas chromatographic analysisfollowing transesterification with 1% w/w NaOMe in methanol at 60° C. tocontain approximately 34 weight % methyl 9-decenoate, approximately 13weight % methyl 9-undecenoate, <1 weight % dimethyl 9-octadecenedioate,and <1 weight % methyl 9-octadecenoate (as determined by gc).

Hydrocarbon olefins were removed from the 5.12 kg of combined reactionproduct described above by vacuum distillation by the general proceduredescribed in example 5. The weight of material remaining after thevolatile olefins were removed was 4.0 kg. An aliquot of the non-volatileproduct mixture was found by gas chromatographic analysis followingtransesterification with 1% w/w NaOMe in methanol at 60° C. to containapproximately 46 weight % methyl 9-decenoate, approximately 18 weight %methyl 9-undecenoate, approximately 2 weight % dimethyl9-octadecenedioate, and approximately 1 weight % methyl 9-octadecenoate(as determined by gc).

Example 10

Two reactions were performed by the general procedures described inexample 8, except that for each reaction, 3.1 kg SBO and 280 mg C848catalyst were used. Following catalyst removal, the reaction productsfrom the two preparations were combined, yielding 5.28 kg of material.An aliquot of the combined product mixture was found by gaschromatographic analysis following transesterification with 1% w/w NaOMein methanol at 60° C. to contain approximately 40 weight % methyl9-decenoate, approximately 13 weight % methyl 9-undecenoate,approximately 2 weight % dimethyl 9-octadecenedioate, and approximately1 weight % methyl 9-octadecenoate (as determined by gc).

Hydrocarbon olefins were removed from the 5.28 kg of combined reactionproduct by vacuum distillation by the general procedure described inexample 5. The weight of material remaining after the volatile olefinswere removed was 4.02 kg. An aliquot of the non-volatile product mixturewas found by gas chromatographic analysis following transesterificationwith 1% w/w NaOMe in methanol at 60° C. to contain approximately 49weight % methyl 9-decenoate, approximately 16 weight % methyl9-undecenoate, approximately 2 weight % dimethyl 9-octadecenedioate, andapproximately 3 weight % methyl 9-octadecenoate (as determined by gc).

Example 11

By the general procedures described in example 10, two metathesisreactions were performed using SBO, 7 mol cis-2-butene/mol SBO doublebond, and 220 mg C848 catalyst/kg SBO. Following catalyst removal, thereaction products from the two preparations were combined, yielding 12.2kg of material. An aliquot of the combined product mixture was found bygas chromatographic analysis following transesterification with 1% w/wNaOMe in methanol at 60° C. to contain approximately 49 weight % methyl9-undecenoate, approximately 2 weight % dimethyl 9-octadecenedioate, andapproximately 1 weight % methyl 9-octadecenoate (as determined by gc).

Hydrocarbon olefins were removed from the 12.2 kg of combined reactionproduct by vacuum distillation by the general procedure described inexample 5. The weight of material remaining after the volatile olefinswere removed was 7.0 kg. An aliquot of the non-volatile product mixturewas found by gas chromatographic analysis following transesterificationwith 1% w/w NaOMe in methanol at 60° C. to contain approximately 57weight % methyl 9-undecenoate, approximately 4 weight % dimethyl9-octadecenedioate, and approximately 2 weight % methyl 9-octadecenoate(as determined by gc).

Example 12

By the general procedures described in example 1, approximately 7 kg ofcross metathesis product was produced by reacting SBO with 3 mol1-butene/mol SBO double bond using 43 mg C827 catalyst/kg SBO, followingcatalyst removal with THMP. An initial 2.09 kg portion of the metathesisproduct was hydrogenated at 136° C. and 400 psig H₂ until hydrogenuptake ceased in a one gallon batch autoclave using 105 g ofJohnson-Matthey A-7000 Sponge Metal™ catalyst. The resulting mixture wasfiltered warm (22-55° C.), yielding 1.40 kg filtrate and 350 g of amixture consisting of the catalyst and the hydrogenated product. Theentirety of the catalyst-containing mixture was returned to the onegallon reactor along with a second 2.18 kg portion of the metathesisproduct and a second hydrogenation reaction was similarly carried outuntil hydrogen uptake ceased. The catalyst was allowed to settle and themajority of the organic product was decanted and filtered, yielding 1.99kg filtrate and 380 g catalyst-hydrogenated product mixture. Theremaining approximately 3 kg of metathesis product was hydrogenated intwo additional batch reactions that in like manner were carried outusing the catalyst from the previous reaction, yielding 1.65 kg and 1.28kg of hydrogenated product, respectively. The total weight ofhydrogenated product that was isolated after filtration was 6.32 kg.Aliquots of the hydrogenated product were found by gas chromatographicanalysis to contain approximately 30 weight % C₆-C₁₈ n-paraffins andapproximately 70 weight % triglycerides. The relative distribution ofthe C₈-C₁₈ n-paraffins contained in the hydrogenated product compareswell with the calculated distribution of olefins by carbon number:observed (calculated) 2.3 (0.6) weight % C₈, 35.6 (36.2) weight % C₉,30.0 (27.6) weight % C₁₀, 0.6 (0.1) weight % C₁₁, 22.2 (23.6) weight %C₁₂, 3.4 (3.7) weight % C₁₃, 0.1 (0.0) weight % C₁₄, 4.4 (6.3) weight %C₁₅, 0.4 (0.4) weight % C₁₆, 0.1 (0.0) weight % C₁₇, and 1.0 (1.6)weight % C₁₈.

The paraffin components were separated by wiped film evaporation from a4.84 kg aliquot of the hydrogenated paraffin/triglyceride product. Aninitial wiped film evaporation was carried out at 75° C., 100 torr, 300rpm, and condensation temperature of 15° C. using a feed rate of 300 g/hand yielded a condensate that was subjected to a second wiped filmevaporation at 125° C., 90 torr, 300 rpm, and condensation temperatureof 10° C. to remove the lighter alkanes. The resultant residual liquidwas found by gas chromatography to contain the following distribution ofn-alkanes: 17.5 weight % C₇, 1.7 weight % C₈, 31.0 weight % C₉, 28.3weight % C₁₀, 0.6 weight % C₁₁, 17.4 weight % C₁₂, 2.1 weight % C₁₃, 0.1weight % C₁₄, 1.2 weight % C₁₅, 0.1 weight % C₁₆, 0.0 weight % C₁₇, and0.1 weight % C₁₈. The material was found to have a heat of combustion of43.86 MJ/kg (ASTM D3338), less than 1 mg/kg sulfur (ASTM D5453), densityof 0.7247 (ASTM D4052), and a final boiling point of 232.3° C. (ASTMD86), indicating the majority of this material would be suitable as ablend stock in a fuel application such as diesel or jet fuel.

Example 13

An oligomerization reaction of 1-olefin/1,4-diene (92 wt % 1-decene, 4.5wt % 1,4-decadiene, 2 wt % 1,4-undecadiene) that was produced from thecross metathesis of palm oil with 1-octene was performed on a 550 gscale using 1.1 mol % ethyl aluminum dichloride (1M solution inhexane)/1.1 mol % tert-butyl chloride for 3 hours at 10° C. The reactionmixture was quenched with water and 1M sodium hydroxide solution andstirred until it became colorless. Hexane (300 ml) was added and mixturewas transferred to a separatory funnel. The organic layer was washedwith water and brine, and then concentrated on a rotary evaporator toremove the hexane. The oligomeric mixture was devolatilized via shortpath vacuum distillation (100° C. and 5 Torr) and the productdistribution was determined to be 97% mixture oligomers by GC/MS. Thedynamic viscosity (Brookfield, #34 spindle, 100 rpm, 22° C.) of thesample is 540 cps. The kinematic viscosity for the sample at 40° C. is232 cSt.

The aforementioned examples utilized the following analytical methodsdescribed below:

Volatile products were analyzed by gas chromatography and flameionization detector (FID). Alkene analyses were performed using anAgilent 6890 instrument and the following conditions:

-   -   Column: Restek Rtx-5, 30 m×0.25 mm (ID)×0.25 μm film thickness    -   Injector temperature: 250° C.    -   Detector temperature: 280° C.    -   Oven temperature: 35° C. starting temperature, 4 minute hold        time, ramp rate 12° C./min to 260° C., 8 minute hold time    -   Carrier gas: Helium    -   Mean gas velocity: 31.3±3.5% cm/sec (calculated)    -   Split ratio: ˜50:1

The products were characterized by comparing peaks with known standards,in conjunction with supporting data from mass spectrum analysis(GCMS-Agilent 5973N). GCMS analysis was accomplished with a secondRtx-5, 30 m×0.25 mm (ID)×0.25 μm film thickness GC column, using thesame method as above.

Alkane analyses were performed using an Agilent 6850 instrument and thefollowing conditions:

-   -   Column: Restek Rtx-65, 30 m×0.32 mm (ID)×0.1 μm film thickness    -   Injector temperature: 250° C.    -   Detector temperature: 350° C.    -   Oven temperature: 55° C. starting temperature, 5 minute hold        time, ramp rate 20° C./min to 350° C., 10 minute hold time    -   Carrier gas: Hydrogen    -   Flow rate: 1.0 mL/min    -   Split ratio: 40:1

The products were characterized by comparing peaks with known standards.Fatty acid methyl ester (FAME) analyses were performed using an Agilent6850 instrument and the following conditions:

-   -   Column: J&W Scientific, DB-Wax, 30 m×0.32 mm (ID)×0.5 μm film        thickness    -   Injector temperature: 250° C.    -   Detector temperature: 300° C.    -   Oven temperature: 70° C. starting temperature, 1 minute hold        time, ramp rate 20° C./min to 180° C., ramp rate 3° C./min to        220° C., 10 minute hold time    -   Carrier gas: Hydrogen    -   Flow rate: 1.0 mL/min

The examples above collectively demonstrate the major steps described inthe process schemes, showing the production of olefins, paraffins,metathesized triglycerides, unsaturated fatty acid esters and acids, anddiacid compounds from natural oils that are useful as chemicals,solvents and fuels blending stocks.

1-28. (canceled)
 29. A method of producing a fuel compositioncomprising: providing a feedstock comprising natural oil glycerides, and(b) low-molecular-weight olefins; reacting the natural oil glycerideswith the low-molecular-weight olefins in the presence of a metathesiscatalyst to form a metathesized product comprising metathesized olefinsand metathesized esters; hydrogenating the metathesized product to forma hydrogenated composition comprising hydrogenated metathesized olefinsand hydrogenated metathesized esters; and separating at least a portionof the hydrogenated metathesized olefins from hydrogenated compositionto form a separated hydrogenated metathesized olefin composition. 30.The method of claim 29, further comprising isomerizing the separatedhydrogenated metathesized olefin composition, which comprisesnormal-paraffin compounds, wherein a fraction of normal-paraffincompounds in the composition are isomerized into iso-paraffin compounds.31. The method of claim 29, wherein the separated hydrogenatedmetathesized olefin composition comprises C₁₈₊ heavy compounds, andfurther comprising separating the C₁₈₊ heavy compounds from thecomposition to form a separated stream comprising C₁₈₊ heavy compounds,the separated stream having a majority of hydrocarbons with carbonnumbers of at least
 18. 32. The method of claim 29, wherein thelow-molecular-weight olefins comprise olefins selected from the groupconsisting of ethylene, propylene, 1-butene, 2-butene, and combinationsthereof.